cryptography - Explain Key Block and master secret with padding and encrytion in SSL/TLS? -

how see encrypted key in wireshark, during ssl key exchange?

referring this answer question:

could explain why pre-master encrypted 128 bits, how rsa public key of 2048 bits encrypt 48 bits data 128 bits, because client , server confirms , use symmetric encryption after change_cipher_spec record.

the key expanded 136 bits, master secret padded , used in encryption.

can explain use/generation of "key-block" in ssl/tls ?

why have client_write_key , server_write_key if using symmetric encryption, wouldn't single key used both encryption , decryption.

and having 2 different mac keys, produce same result message send authenticated if securely client , server , not exchanged.

could explain why pre-master encrypted 128 bits, how rsa public key of 2048 bits encrypt 48 bits data 128 bits

it doesn't. pre-master secret 48 bytes, , encryption 128 bytes, including padding, , public key length of 2048 bits has nothing that.

because client , server confirms , use symmetric encryption after change_cipher_spec record.

correct. so?

the key expanded 136 bits, master secret padded , used in encryption.

the key expansion 136 bytes; not master secret; , used generate symmetric session key , ivs.

can explain use/generation of "key-block" in ssl/tls?

never heard of it. term 'key-block' not appear in rfc 2246.

why have client_write_key , server_write_key if using symmetric encryption, wouldn't single key used both encryption , decryption.

apparently different key used in each direction.

and having 2 different mac keys, produce same result message send authenticated if securely client , server , not exchanged.

please define 'securely client , server'.

to answer these questions should see rfc 2246 #6.3 key calculation. it's pretty pointless paraphrase here. don't intend attempt it.